PROFESSOR TYNDALL’S CONTRIBUTIONS TO MOLECULAR PHYSICS. 339 
heat, and from these, and the vapour-densities, we can immediately deduce the corre- 
sponding volumes of the vapour. Calling the quantity of matter g, the vapour-density d, 
and the volume V, we have 
Dividing, therefore, the specific gravities of our liquids by the densities of their vapours, 
we obtain a series of volumes proportional to the masses of the liquids employed. The 
densities of both liquids and vapours are given in the following Table 
Table of Densities. 
Vapour. 
Liquid. 
Bisulphide of Carbon . 
. . 2-63 
1-27 
Chloroform .... 
. . 4-13 
1-48 
Iodide of Methyl . . . 
. . 4-90 
2-24 
Iodide of Ethyl . . . 
. . 5-39 
1-95 
Benzol 
. . 2-69 
0*85 
Amylene 
. . 2-42 
0-64 
Alcohol 
. . 1-59 
0-79 
Sulphuric Ether . . . 
. . 2-56 
0*71 
Formic Ether .... 
. . 2-56 
0-91 
Acetic Ether .... 
. . 3-04 
0-89 
Water 
. . 0*63 
1-00 
Substituting for q the numbers of the second column, and for d those of the first, we 
obtain the following series of vapour volumes, whose weights are proportional to the 
masses of liquid employed. 
Table of Proportional Volumes. 
Bisulphide of Carbon . . . . 0-48 
Chloroform ....... 0*36 
Iodide of Methyl 0*46 
Iodide of Ethyl 0'36 
Benzol 0 - 32 
Amylene 0’26 
Alcohol 0’50 
Sulphuric Ether 0-28 
Formic Ether O’ 36 
Acetic Ether 0*29 
Water 1*60 
Employing the vapours in the volumes here indicated, the 
obtained : — - 
following results were 
